Multifunction interface facility connecting wideband multiple access subscriber loops with various networks

ABSTRACT

An device, called a facilities management platform (FMP) connects current digital and analog carrier networks and packet switched networks of interexchange carriers with high speed multiple access subscriber links implemented over twisted pair lines. The subscriber line is terminated by an access module containing one or more modems. In preferred embodiments, the modems are high-speed digital tethered vial radio channel or xDSL modems. The FMP interface applies and receives signaling and voice through a digital loop carrier (DLC) via a multiplexer connected directly to the DLC backplane. The multiplexer is controlled by a controller of an access module. It translates data from the subscriber link to the form compatible with the digital backplane to create the appearance of one or more line cards. The FMP also may contain a sound generator to allow it to handle calls through an analog carrier network. The FMP, through the same access module transmits data to and from the modems directly through connected digital networks, such as ATM or SONET, of an interexchange carrier. Through this interface, different network companies can offer competing products through different networks all seamlessly connected through a high speed subscriber line.

This application is a continuation of U.S. patent application Ser. No.09/001,422, filed Dec. 31, 1997 now U.S. Pat. No. 6,363,079, by the sameinventors and similarly titled.

FIELD OF THE INVENTION

This invention discloses a wideband communications link layer interfacebetween the digital networks employed by interexchange carriers and newwideband local loop systems connecting subscribers. For example, theinvention relates to an interface for tethered radio channel (e.g.,digital subscriber loops) local loops to homes and businesses thatprovide multiple voice and data channels over twisted pair media.

BACKGROUND OF THE INVENTION

As deregulation of the telephone industry continues and as companiesprepare to enter the local telephone access market, there is a need tooffer new and innovative services that distinguish common carriers fromtheir competitors. This cannot be accomplished without introducing newlocal access network architectures that will be able to support thesenew and innovative services.

Conventionally, customer premises telephone and/or data connectionscontain splitters for separating analog voice calls from other dataservices such as Ethernet transported over digital subscriber line (DSL)modems. Voice band data and voice signals are sent through acommunications switch in a central or local office to an interexchangecarrier or Internet service provider. DSL data is sent through a digitalsubscriber loop asynchronous mode (DSLAM) switch which may include arouter. The DSLAM switch connects many lines and routes the digital datato a telephone company's digital switch.

A major problem with this configuration is that interexchange carriersattempting to penetrate the local telephone company's territory mustlease trunk lines from the local telephone company switch to theinterexchange company's network for digital traffic. Furthermore, theInternet service provider must lease a modem from the local phonecompany in the DSLAM switch and route its data through the local phonecompany's digital switch. Thus, the local phone company leases and/orprovides a significant amount of equipment, driving up the cost of entryfor any other company trying to provide local telephone services andmaking it difficult for the interexchange companies to differentiatetheir services. Furthermore, since DSL modem technology is notstandardized, in order to ensure compatibility, the DSL modem providedby the local telephone company must also be provided to the end user inthe customer premises equipment (CPE). Additionally, since the networkis not completely controlled by the interexchange companies, it isdifficult to for the interexchange companies to provide data atcommitted deliver rates. Any performance improvements implemented by theinterexchange companies may not be realized by their customers, becausethe capabilities of the local telephone company equipment may or may notmeet their performance needs. Thus, it is difficult for theinterexchange companies to convince potential customers to switch totheir equipment or to use their services. These factors ensure thecontinued market presence of the local telephone company.

As part of this system, there is a need for improved architectures,services and equipment utilized to allow the interexchange companies tooffer more products and services to customers. DSL technology, one typeof communication system that can use conventional twisted pair wiring,for which a large infrastcture is in place, holds the promise ofproviding high bandwidth communication into any telephone subscriber'shome or business. However, support for such high speed communicationbetween the existing and future networks and the local high speed loopspresent major problems: For example, how can such new technology beinterfaced with existing and future interexchange carrier equipment andsoftware in a way that allows future growth? How do existing services,such as voice, facsimile, and modem communications fit into the schemeif the twisted pair formerly used for such purposes is co-opted by a newDSL-based system (for example)? How can such an interface take fulladvantage of the promise of wide-band connection to homes and businesseswithout being hamstrung by the need to interface with conventionaltechnology? How can the huge burden of wide-band communication tosubscriber's premises be handled by interexchange carriers? For example,if people can watch movies at home, how can numerous moves betransmitted from far-flung sites without overtaxing even futureinterexchange carrier infrastructure?

SUMMARY OF THE INVENTION

In order to provide an improved network, it is desirable for theinterexchange companies to have access to at least one of thetwisted-pair lines connecting each of the individual users to the localtelephone network before the lines are routed through the conventionallocal telephone network equipment. It is preferable to have access tothese lines prior to the splitter and modem technology offered by thelocal service providers. By having access to the twisted-pair wiresentering the customer's premises, interexchange companies can offerbetter services by providing higher bandwidth, improving thecapabilities of the customer premises equipment, and lowering overallsystem costs to the customer by enhancing competition between localexchange carriers and interexchange carriers.

The new architecture may utilize a video phone and/or other devices toprovide new services to an end user, an intelligent services director(ISD) disposed near the customer's premises for multiplexing andcoordinating many digital services onto a single twisted-pair line; afacilities management platform (FMP) disposed in the local telephonenetwork's central office for routing data to an appropriateinterexchange company network; and a network server platform (NSP)coupled to the FMP for providing new and innovative services to thecustomer and for distinguishing services provided by the interexchangecompanies from those services provided by the local telephone network.

As part of this system, one aspect of the invention provides a so-calledFMP which provides a link between the local loop to the customerpremises ISD (which may also be located remotely from the customerpremises) and the interexchange company network.

Briefly, in summary, the FMP connects current digital and analog carriernetworks and packet switched networks of interexchange carriers withhigh speed multiple access subscriber links implemented over twistedpair lines. The subscriber line is terminated by an access modulecontaining one or more modems. In preferred embodiments, the modems arehigh-speed digital tethered virtual radio channel or xDSL modems. Theinterface applies and receives signaling and voice through a digitalloop carrier (DLC) via a multiplexer connected directly to the DLCbackplane. The multiplexer is controlled by a controller of an accessmodule. It translates data from the subscriber link to the formcompatible with the digital backplane to create the appearance of one ormore line cards. The FMP also may contain a sound generator to allow itto handle calls through an analog carrier network. The FMP, through thesame access module transmits data to and from the modems directlythrough connected digital networks, such as ATM or SONET, of aninterexchange carrier. Through this interface, different networkcompanies can offer competing products through different networks allseamlessly connected through a high speed subscriber line.

According to one embodiment, the invention is a telecommunicationsinterface for communicating subscriber data containing voice, andsignaling, and user data between (1) a digital network, (2) a digitalloop carrier having an analog interface to connect telephones and adigital circuit connecting the telephone switch to other telephoneswitches, and (3) a subscriber link to equipment at a subscriber'spremise. The interface has a controller and a modem. The modem modulatesand demodulates the subscriber data to and from the subscriber link togenerate a digital stream containing the voice, and signaling, and userdata. A digital filter separates the voice data from the digital stream.The controller applies the voice data to the digital circuit when thesignaling data indicates the voice data is to be transmitted by thedigital circuit. When the signaling data indicates the voice data is tobe transmitted over the digital network, however, the controller appliesthe voice data to the digital network.

According to another embodiment, the invention is a central officeinterface between a multiple access link, established over a singletwisted pair metallic interface, to a subscriber premises and a localcarrier network A digital loop carrier with a digital interface permitsaccess to a digital backplane of the digital loop carrier. A controllerwith a modulator/demodulator applies voice and signaling datacorresponding to multiple voice call sessions from the link to thedigital interface. In the reverse direction, it also applies datacorresponding to the multiple voice call sessions from the digitalinterface to the link.

According to still another embodiment, the invention is a method ofconnecting telecommunication call sessions from multiple stations at asubscriber premise, which is accomplished by generating signaling dataat one of the stations and transmitting the signaling data over themultiple access link to the network interface. In response to receivingthe signaling data at the network interface, the signaling data istransmitted over one of a digital loop carrier and a digital networkdepending on a called number in the signaling data. Then a channel isallocated in a multiple access link to a network interface tocommunicate data over the link, the user data corresponding to thesignaling data and the channel deallocated in response to a terminationof the user data.

In another embodiment, the invention provides a method of connectingtelecommunication call sessions from multiple stations at a subscriberpremise through a multiple access subscriber link. The following stepsare performed: providing a digital interface to a backplane of a digitalloop carrier, generating signaling data at a one of the stations;transmitting the signaling data over the multiple access link to thenetwork interface; in response to receiving the signaling data at thenetwork interface, applying the signaling data to the digital interfaceto create an appearance of a POT connected through a line card connectedto the backplane.

In another embodiment, the invention provides a method of connectingtelecommunication call sessions from multiple stations at a subscriberpremise through a multiple access subscriber link. The method includesthe following steps: providing a digital interface to a backplane of adigital loop carrier, generating signaling data at a one of thestations; transmitting the signaling data over the multiple access linkto the network interface; generating DTMF tones and applying the tonesto a telecommunications switch responsively to the signaling data andthen subsequently connecting a call initiated at the one of the stationsthrough a channel opened up in the step of applying the tones;generating further signaling data at another one of the stationstransmitting the further signaling data over the multiple access link tothe network interface; setting up a call session for transmissionthrough a virtual channel of a digital network connected to the networkinterface (the step of setting up a call including transmitting arequest on a signaling channel of the digital network for bandwidthrequired for a call corresponding to the signaling data); and applyingsubsequent voice data in a virtual channel responsively to a result ofthe step of transmitting a request.

According to still another embodiment, the invention provides a methodof connecting telecommunication call sessions from multiple stations ata subscriber premise through a multiple access subscriber link. Thefollowing steps are included in the method. An indication of aninitiation of a voice-dialing call at one of the stations is generated(for example, a phone is picked up for a period of time withoutdialing). This indication is transmitted through the link to networkinterface and, upon receipt of the indication at the network interface,a channel is opened in a digital network. Voice data corresponding tothe called number are transmitted through the channel to a server of thenetwork. The server determines the called number and sends it to thenetwork interface. The network interface then connects a call based onthe signaling data.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing summary of the invention, as well as the followingdetailed description of preferred embodiments, is better understood whenread in conjunction with the accompanying drawings, which are includedby way of example, and not by way of limitation with regard to theclaimed invention.

In the drawing,

FIG. 1 illustrates an embodiment of a hybrid fiber twisted pair localloop architecture.

FIG. 2 is a block diagram of an embodiment of an intelligent servicesdirector consistent with the architecture shown in FIG. 1.

FIGS. 3A and 3B illustrate an embodiment of a video phone consistentwith the architecture shown in FIG. 1.

FIG. 4A is a block diagram of an embodiment of a facilities managementplatform consistent with the architecture shown in FIG. 1.

FIG. 4A1 is a block diagram of the embodiment of FIG. 4A modified by theaddition of an internal cache system.

FIG. 4B illustrates a block diagram of an embodiment of a network serverplatform consistent with the architecture shown in FIG. 1.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The following description provides an overview of how the primarysubject of this application, the facilities management platform (FMP),fits into a communication network. Referring to FIG. 1, a firstexemplary communication network architecture employing a hybrid fiber,twisted-pair (HFTP) local loop 1 architecture is shown. An intelligentservices director (ISD) 22 may be coupled to a central office 34 via atwisted-pair wire 30, a connector block 26, and/or a main distributionframe (MDF) 28. The ISD 22 and the central or local office 34 maycommunicate with each other using, for example, framed, time division,frequency-division, synchronous, asynchronous and/or spread spectrumformats, but in exemplary embodiments uses DSL modem technology. Thecentral office 34 preferably includes a facilities management platform(FMP) 32 for processing data exchanged across the twisted-pair wire 30.The FMP 32 may be configured to support plain old telephone service(POTS) by handling voice signals digitized by the ISD 22 in variousways. Voice data can be multiplexed directly onto the digital backplaneof a PSTN or modified digital loop carrier or it can be formatted fortransmission directly on a digital (for example, interexchange) networkwhich may be optical or ATM. Ultimately voice data may be received by aremote PSTN 46 and transmitted to a called party or through a remote FMP32 to the called party. Demodulation of the subscriber link signal(e.g., DSL) is handled by a, for example, tethered virtual radio channel(TVRC) modem (shown in FIG. 4A). Non-voice data may be output to a highspeed backbone network (e.g., a fiber-optic network) such as anasynchronous transfer mode (ATM switching network.

The FMP 32 may process data and/or analog/digitized voice betweencustomer premise equipment (CPE) 10 and any number of networks. Forexample, the FMP 32 may be interconnected with a synchronous opticalnetwork (SONET) 42 for interconnection to any number of additionalnetworks such as an InterSpan backbone 48, the PSTN 46, a public switchswitching network (e.g. call setup SS7-type network 44), and/or anetwork server platform (NSP) 36. Alternatively, the FMP 32 may bedirectly connected to any of these networks. One or more FMPs 32 may beconnected directly to the high speed backbone network (e.g., directfiber connection with the SONET network 42) or they may be linked via atrunk line (e.g., trunks 40 or 42) to one or more additional networks.FMP 32 may also interconnect with other FMP 32 units to limit traffic onother network facilities for calls destined for nearby FMPs 32.Moreover, calls between two subscribers linked to the same FMP 32 maycommunicate through the FMP 32 without being linked to any of the othernetwork facilities. In addition, the FMP 32 may provide internal cachingto limit the burden on the external network facilities. For example, amovie might be cached during certain time of the day if one particularmovie is being requested by many subscribers at around the same time.

Although the possibly massive demands of a cache for user data may makeit economically unfeasible to cache data such as movies, the FMP 32would, preferably, have an internal memory or other data storage thatwould contain information about each subscriber to which it is linked.For example, a subscriber may not subscribe to all the services the FMP32 makes available. For example, one subscriber might want its calls,where possible, handled by the interexchange carrier by directly routingthem through one of the digital networks (e.g., ATM) owned by theinterexchange carrier or other owner of the FMP 32. Another subscribermay prefer to go through the local phone company through the modifiedDLC 70 for at least some calls depending on the pricing and featuresoffered by the competing carriers. This data is preferably stored onsuch an internal storage at the FM 32. Such data could be updated by theNSP 46 as required. Storing such data, aside from saving bandwidth ofexternal networks, will also speed the handling of calls.

The NSP 36 may provide a massive cache storage for various informationthat may be provided across the SONET net 42 to the FMP 32 and out tothe ISD 22. The NSP 36 and the FMP 32 may collectively define an accessnetwork server complex 38. The NSP 36 may be interconnected withmultiple FMPs 32. Furthermore, each FMP 32 may interconnect with one ormore ISDs 22. The NSP 36 may be located anywhere but is preferablylocated in a point-of-presence facility. The NSP 36 may further act as agateway to, for example, any number of additional services. The majortasks of the NSP 46 is to handle connection management, act as anapplication launcher and provide operations administration maintenance &provisioning.

The ISD 22 may be interconnected to various devices such as a videophone130, other digital phones 18, set-top devices, computers, and/or otherdevices comprising the customer premise equipment 10. The customerpremise equipment 10 may individually or collectively serve as a localnetwork computer at the customer site. Applets may be downloaded fromthe NSP 36 into some or all of the individual devices within thecustomer premise equipment 10. Where applets are provided by the NSP 36,the programming of the applets may be updated such that the applets arebe continually configured to the latest software version by theinterexchange carrier. In this way, the CPE 10 may be kept up to date bysimply re-loading updated applets. In addition, certain applets may beresident on any of the CPE 10. These resident applets may beperiodically reinitialized by simply sending a request from, forexample, a digital phone 18 and/or a videophone 130 to the FMP 32 andthereafter to the NSP 36 for reinitialization and downloading of newapplets. To ensure wide spread availability of the new features madepossible by the present architecture, the customer premise equipment maybe provided to end users either at a subsidized cost or given away forfree, with the cost of the equipment being amortized over the servicessold to the user through the equipment.

Referring to FIG. 2, the ISD 22 may connect with a variety of devicesincluding analog and digital voice telephones 15, 18; digitalvideophones 130, devices for monitoring home security, meter readingdevices (not shown), utilities devices (not shown), facsimile devices16, personal computers 14, and/or other digital or analog devices. Someor all of these devices may be connected with the ISD 22 via anysuitable mechanism such as a single and/or multiple twisted-pair wiresand/or a wireless connection. For example, a number of digital devicesmay be multi-dropped on a single twisted-pair connection. Similarly,analog phones and other analog devices may be multi-dropped usingconventional techniques.

The ISD 22 may be located within the home/business or mounted exteriorto the home/business. The ISD 22 may operate from electrical powersupplied by the local or central office 34 and/or from the customer'spower supplied by the customer's power company. Where the ISD 22includes a modem, it may be desirable to power the ISD 22 withsupplemental power from the home in order to provide sufficient power toenable the optimal operation of the modem.

As shown in FIG. 2, in some embodiments the ISD 22 may include acontroller 100 which may have any of a variety of elements such as acentral processing unit 102, a DRAM 103, an SRAM 104, a ROM 105 and/oran internet protocol (IP) bridge router 106 connecting the controller100 to a system bus 111. The system bus 111 may be connected with avariety of network interface devices 110. The network interface devices110 may be variously configured to include an integrated servicesdigital network (ISDN) interface 113, an Ethernet interface 119 (e.g.,for 28.8 kbs data, 56 kbs data, or ISDN), an IEEE 1394 “fire wire”interface 112 (e.g., for digital a videodisc device (DVD)), a TVRC modeminterface 114 (e.g., for a digital subscriber line (DSL) modem), aresidential interface 114, (e.g., standard POTS phone systems such astip ring), a business interface 116 (e.g., a T1 line and/or PABXinterface), a radio frequency (RF) audio/video interface 120 (e.g., acable television connection), and a cordless phone interface 123 (e.g.,a 900 MHZ transceiver). Connected to one of the network interfacesand/or the system bus 111 may be any number of devices such as an audiointerface 122 (e.g., for digital audio, digital telephones, digitalaudio tape (DAT) recorders/players, music for restaurants, MIDIinterface, DVD, etc.), a digital phone 121, a videophone/user interface130, a television set-top device 131 and/or other devices. Where thenetwork interface is utilized, it may be desirable to use, for example,the IEEE 1394 interface 112 and/or the Ethernet interface 119.

A lifeline 126 may be provided for continuous telephone service in theevent of a power failure at the CPE 10. The lifeline 126 may be utilizedto connect the ISD 22 to the local telecommunications company's centraloffice 34 and, in particular, to the FMP 32 located in the centraloffice 34.

The ISD 22 may be variously configured to provide any number of suitableservices. For example, the ISD 22 may offer high fidelity radio channelsby allowing the user to select a particular channel and obtaining adigitized radio channel from a remote location and outputting thedigital audio, for example, on audio interface 122, video phone 130,and/or digital phones 121. A digital telephone may be connected to theaudio interface 122 such that a user may select any one of a number ofdigital radio cable channels by simply having the user push a cablechannel button on the telephone and have the speaker phone outputparticular channels. The telephone may be preprogramed to provide theradio channels at a particular time, such as a wake up call for bedroommounted telephone, or elsewhere in the house. The user may select anynumber of services on the video phone and/or other user interface suchas a cable set-top device. These services may include any number ofsuitable services such as weather, headlines in the news, stock quotes,neighborhood community services information, ticket information,restaurant information, service directories (e.g., yellow pages), callconferencing, billing systems, mailing systems, coupons, advertisements,maps, classes, Internet, pay-per-view (PPV), and/or other services usingany suitable user interface such as the audio interface 122, the videophone/user interface 130, digital phones, 121 and/or another suitabledevice such as a settop 131.

In further embodiments, the ISD 22 may be configured as an IP proxyserver such that each of the devices connected to the server utilizetransmission control protocol/internet protocol (TCP/IP) protocol. Thisconfiguration allows any device associated with the ISD 22 to access theInternet via an IP connection through the FMP 32. Where the ISD 22 isconfigured as an IP proxy server, it may accommodate additional devicesthat do not support the TCP/IP protocol. In this embodiment, the ISD 22may have a proprietary or conventional interface connecting the ISD 22to any associated device such as to the set top box 131, the personalcomputer 14, the video telephone 130, the digital telephone 18, and/orsome other end user device.

The FMP 32 may also be configured to function as an IP proxy server. Theprotocal between the FMP 23 and ISD22 is not restricted in this case asit would be if the ISD functioned as the IP proxy server. In eithercase, whether the ISD 22 or the FMP 32 functions as the IP proxy server,the possibility of permitting telephone calls from any phone linkedthrough the ISD22 for internet telephony becomes possible. A callerdials a number from, preferably from a telephone that provides menu andfunction buttons from the telephone, such as the videophone described inthe related applications incorporated by reference. The user wouldindicate to the ISD whether a call was to be handled through anarrowband network (such as typically provides dedicated 64 Khzbandwidth through switches) or a broadband network such as apacket-switched network (e.g., ATM, SONET, an internet backbone, etc).Since the broadband service is likely to be less costly, although theservice may not be as good, the user is able to trade a lower qualitybut cheaper service for a high quality service that costs more. Thisdecision can be made automatically through the NSP (see discussion ofNSP functionality in this specification and related applicationsincorporated by reference). A caller dials a number. The signaling data(containing the number) is sent to the NSP which looks up the number ina table of user preferences and determines the called number is to behandled through a broadband network. The NSP 46 sends a message back toeither the FMP 32 or the ISD 22, whichever is set up as the proxyserver, and the FMP 32 or ISD22 responds by routing the callappropriately (and, of course, packaging the voice data as appropriateto the type of network).

Although the features discussed above are contemplated in terms of theinternet context and IP protocol, they apply to any kind of broadbandnetwork. Thus, the FMP 32 or ISD 22 can package voice data appropriatelyfor any broadband network selectively according to user preferene asoutlined above.

In still further embodiments, the ISD 22 may be compatible withmulticast broadcast services where multicast information is broadcast bya central location and/or other server on one of the networks connectedto the FMP 32, e.g., an ATM-switched network. The ISD 22 may downloadthe multicast information via the FMP 32 to any of the devices connectedto the ISD 22. The ISD 22 and/or CPE 10 devices may selectively filterthe information in accordance with a specific customer user'spreferences. For example, one user may select all country musicbroadcasts on a particular day while another user may select financialinformation. The ISD 22 and/or any of the CPE 10 devices may also beprogrammed to store information representing users'preferences and/orthe received uni-cast or multicast information in memory or otherstorage media for later replay. Thus, for example, video clips or moviesmay be multicast to all customers in the community with certain usersbeing preconfigured to select the desired video clip/movie in real timefor immediate viewing and/or into storage for later viewing.

Referring to FIG. 3A, a videophone 130 may include a touch screendisplay 141 and soft keys 142 around the perimeter of the display 141.The display may be responsive to touch, pressure, and/or light input.Some or all of the soft keys 142 may be programmable and may vary infunction depending upon, for example, the applet being run by thevideophone 130. The function of each soft key may be displayed next tothe key on the display 141. The functions of the soft keys 142 may alsobe manually changed by the user by pressing scroll buttons 143. Thevideophone 140 may also include a handset 144 (which may be connectedvia a cord or wireless connection to the rest of the videophone and/ordirectly to the ISD), a keypad 150, a video camera 145, a credit cardreader 146, a smart card slot 147, a microphone 149, a motion and/orlight detector 148, built-in speaker(s) 155, a printer/scanner/facsimile152, and/or external speakers 154 (e.g., stereo speakers). A keyboard153 and/or a postage scale 151 may also be connected to the videophone130. Any or all of the above-mentioned items may be integrated with thevideophone unit itself or may be physically separate from the videophoneunit. A block diagram of the video phone unit is shown in FIG. 3B.Referring to FIG. 3B, in addition to the items above, the video phone130 may also include a signal processor 171, high speed interfacecircuitry 172, memory 173, power supply 174, all interconnected via acontroller 170.

When the videophone 130 is used as a video telephone, the display 141may include one or more video window(s) 160 for viewing a person to whoma user is speaking and/or showing the picture seen by the person on theother end of the video phone. The display may also include adialed-telephone-number window 161 for displaying the phone numberdialed, a virtual keypad 162, virtual buttons 163 for performing varioustelephone functions, service directory icons 165, a mail icon 164,and/or various other service icons 166 which may be used, for example,for obtaining coupons or connecting with an operator. Any or all ofthese items may be displayed as virtual buttons and/or graphic icons andmay be arranged in any combination. Additionally, any number of otherdisplay features may be shown on the video phone in accordance with oneor more of the applications incorporated by reference below.

Referring to FIG. 4A, the FMP 32 may coordinate the flow of datapackets, separate voice signals from other signals, perform linemonitoring and switching functions, and/or convert between analog anddigital signals. The FMP 32 may process data sent from the CPE 10 to thecentral or local office 34 by separating and reconstructing analog voicesignals, data, and control frames. The FMP 32 may process data sent fromthe central or local office 34 to the CPE 10 by separating controlmessages from user information, and configure this information intosegments for transport across the digital subscriber loop. The FMP 32may also terminate all link layers associated with the digitalsubscriber loop.

In some embodiments, the FMP 32 may include an access module 70 and adigital loop carrier 87. The access module 70 may include a lineprotector 71, a cross-connector 73, a plurality of TVRC modems 80, aplurality of digital filters 82, a controller multiplexer 84, and/or arouter and facilities interface 86. The digital loop carrier 87 mayinclude a plurality of line cards 96, a time domain multiplexing (TDM)multiplexer (MUX) 88, a TDM bus 90, a controller 92, and/or a facilitiesinterface 94.

During normal operations, digital signals on the subscriber lines 30(e.g., twisted-pair lines) containing both voice and data may bereceived by the TVRC modems 80 via the line protector 71 and thecross-connector 73. Preferably, the line protector 71 includes lightningblocks for grounding power surges due to lightning or other strayvoltage surges. The TVRC modems 80 may send the digital voice and/ordata signals to the controller multiplexer 84 and the digital filters82. The digital filters 82 may separate the voice signals from thedigital data signals, and the controller multiplexer 84 may thenmultiplex the voice signals and/or data signals received from thedigital filters 82. The controller multiplexer 84 may then sendmultiplexed voice signals to the TDM MUX 88 and the data signals to therouter and facilities interface 86 for transmission to one or moreexternal networks. The TDM MUX 88 may multiplex the voice signals fromthe controller multiplexer 84 and/or send the voice signals to the TDMbus 90, which may then send the digital voice signals to the controller92 and then to the facilities interface 94 for transmission to one ormore external networks. Alternatively, voice data may be repackaged bycontroller & multiplexer 84 for application directly to any of variousdigital networks without going through modified DLC 70. Both the routerand facilities interface 86 and the facilities interface 94 may convertbetween electrical signals and optical signals when a fiber optic linkis utilized.

When there is a failure of the digital data link (e.g., if there is afailure of the TVRC modems 80 at the FMP 32 or the TVRC modem 114 at theISD 22), only analog voice signals might be sent over the subscriberlines 30. In such a case, the analog voice signals may be directlyrouted to the line cards 96, bypassing the TVRC modems 80, the digitalfilters 82, the controller multiplexer 84, and the TDM MUX 88. Thus,voice communication is ensured despite a failure of the digital datalink. The line cards 96 may convert the analog voice signals intodigital format (e.g., TDM format) and send the digitized voice data ontothe TDM bus 90 and eventually through the controller 92 and thefacilities interface 94 for transmission to one or more externalnetworks.

Referring to FIG. 4B, the NSP 36 may be variously configured to provideany number of services provided by a server such as informationservices, Internet services, pay-per-view movie services, data-baseservices, commercial services, and/or other suitable services. In theembodiment shown in FIG. 4B, the NSP 36 includes a router 185 having abackbone 180 (e.g., a fiber distributed data interface (FDDI) backbone)that interconnects a management server 182, an information/databaseserver 183, and/or one or more application server clusters 184. The NSP36 maybe connected via the router 185 by a link 181 to one or moreexternal networks, NSPs 36, and/or an FMPs 32. The information/data baseserver 183 may perform storage and/or database functions. Theapplication server cluster 184 may maintain and control the downloadingof applets to the ISD 22. The NSP 36 may also include a voice/callprocessor. 186 configured to handle call and data routing functions,set-up functions, distributed operating system functions, voicerecognition functions for spoken commands input from any of the ISDconnected devices as well as other functions.

Referring again to FIGS. 1 and 4A, as mentioned, the FMP 32 serves alink-layer termination for the high-speed subscriber data link, forexample, a DSL link between the ISD 22 at a customer premise and thedigital network of an interexchange carrier (shown in FIG. 1). The FMP32 communicates with the ISD 22, receiving signaling data, user data,and voice data over (preferably) a high speed DSL link. The signalingdata tells the FMP 32 how to handle (route) the voice and user data.There are two major routing alternatives, to route as a normal callthrough the modified DLC 70 or to route directly through theinterexchange carrier network by converting the user and voice datadirectly from the format of the subscriber link to the format of theinterexchange carrier network used. In the latter case, a dialoguebetween the FMP 32 and the NSP 46 may be established to inform the NSP46 that a call is impending or terminated and to request that itallocate or deallocate bandwidth of the network accordingly. Thefollowing is a detailed description of the elements of a preferredembodiment of the FMP 32.

FMP 32 receives digital data over a twisted pair connection (preferred,but could be any other medium) which terminates at a line protectionblock 71. In an embodiment, the FMP 32 supports DSL communication withthe ISD 22. The termination to which twisted pair wiring connects theISD 22 with the FMP 32 is responsible for terminating the DSL link. Thisincludes providing Borscht as well as DSL modem functions.

During normal operation the DSL Facilities Termination subsystem isresponsible for providing over-voltage protection. This is the same asin a convention wire termination. In addition, the FMP 32 includes DSLmodems or TVRC modems 80 to convert analog symbols to digital data andvice versa using for example M-PSK or M-QAM modulation/demodulation.These techniques are described in the literature and applicationsincorporated by reference in the present application.

Another function of the FMP 32 is to provide in-servicetesting/monitoring of the ISD facility. This aspect stems from the factthat the FMP 32 stands in the shoes of the DLC it supplements.

On the network side of the modems, data must be framed before beingmodulated to be transmit over the DSL link. Other preparations includeencoding for forward error correction (for data not suited toretransmission such as voice data) and interleaving (to reduce drasticeffects of impulsive noise or fading).

The final output of the- termination/modem subsystem is a stream of DSLframes containing higher-layer protocol data. In the CPR-to-networkdirection. The controller & multiplexer 84 processes the DSL frames itreceives from the Facilities Termination subsystem to terminate any linklayers associated with the DSL segment of the connection, (in anembodiment) re-construct (e.g. IPv6) packets from the DSL frames, andseparate (IP) packets containing voice, data, and signaling(call-routing or data routing) information.

In an embodiment of the invention, for purposes of transmitting voicedata directly from an external digital network (as opposed to throughmodified DLC 70) data containing voice (for example, in voice-packets)are delivered by the controller & multiplexer 84 to a packet-to-circuittranslation subsystem (not shown separately) by an internal networksystem (also not shown separately). User data packets are deliveredto/from the external networks (which can be interexchange carriernetworks or any other external network) and signaling packets to/fromthe subscriber signaling subsystem of the external network where userdata or voice data are routed directly as packets or to/from controller92 where user or voice data are routed through modified DLC 70.

In the network-to-CPE direction, the controller & multiplexer 84processes the packets it receives from all subscriber signaling andexternal routing subsystems. This involves multiplexing (at the packetlevel) voice, data and subscriber signaling packets bound for a singleDSL link. It also involves mapping packets onto DSL frames, andterminating the FMP-side of any link layers associated with the DSLlink. Packets traveling in the network-to-CPE direction are sentdirectly to the DSL termination for delivery to ISD 22.

For purposes of transferring data between its subsystems, such as withinthe controller & multiplexer 84, voice, data, and signaling packets aretransported via an internal routing system (not shown separately) thatis at least logically, and perhaps physically also, distinct from theexternal networks with which the FMP 32 communicates. This is useful forreliability, security, and availability reasons.

In FIG. 4A, various elements of the FMP 32, which could be on a singleplug-in card that accommodates terminations for four subscribers lines,are shown. Each of the four subscribers can be connected to a respective(any) one of five TVRC modems 80 (TVRC or DSL preferred, but could beany type of digital modem) via a cross-connector switch. In the event ofa failure of one of modems the ISD 22 indicated by, for example,irregular communications detected in controller & multiplexer 84 orcontroller 92, cross connector 73 will switch the subscriber from thesuspected bad TVRC modem to a spare one of the five TVRC modems 80. TheFMP 32 could employ failure indicators (not shown) to advise maintenancepersonnel that a modem has been switched out and that it should bereplaced. TVRC modems 80 are high speed digital modems with the abilityto transmit and receive data at rates of 1 Mbit or more using advancedmodulation, error-correction coding, and data compression techniques.These are preferred known technologies and are described in otherreferences including some of the copending applications incorporated byreference in the present application. No particular technology ortechnique is identified with modems 80 and more advanced technologiesmay be employed with the present invention.

The five modem connections to the cross connector 73 are switchable torespective connections to five line cards to provide telephone service(life line service) in the event that the ISD 22 becomes inoperative. Ina conventional digital loop carrier (as opposed to modified DLC 87) theline cards connect over twisted pairs to POTs to interface the digitalbackplane 90 and the analog POTs. In the modified DLC 87, they serve thesame purpose when the line card is switched-in and the TVRC modemswitched-out due to failure of a connected ISD 22. That is, the linecards serve as the terminations of the analog phone lines providingpower to the telephones via a battery, supplying the ringing voltagepower, out of service testing and supervision of the subscriber terminalas well as interfacing the digital communications on the TDM backplane90 to the analog system of the calling/called POT. Thus, in the event offailure of an ISD 22, the FMP, for that particular line, acts like aconventional DLC because the entire access module 70 and its featuresand the modified aspects of the DLC 87 are bypassed. In the event of afailure at the customer premises, battery supply to the subscriber line,out-of-service testing, ringing voltage supply, and supervision ofsubscriber terminals are also provided.

Under normal operation, the TVRC modems 80 demodulate some kind oftone-symbol (e.g., QAM PSK, etc.) on the subscriber lines to generatesubscriber data including voice, signaling, and user data, and apply theresulting data stream to the digital filters 82. As discussed above, thedigital data from the ISDs 22 contain voice, digital information, andsignaling from, potentially, many different subscriber equipment allmultiplexed into the same data stream, preferably a packet-basedprotocol as discussed above. At a time when a call is just being dialedby the user, the data stream will contain signaling information (unlessa voice-activated dialing feature is being used as discussed furtherbelow). At other times, signaling data may be generated automatically bysubscriber equipment such as a settop unit in the process of ordering amovie.

Call setup may be performed in a way that bypasses the normalinteraction between the regular DLC (not shown) and the modified DLC 87because the ISD 22 may send call signaling data as digital informationto the FMP 32. Thus, there may be no need to interpret DTMF tones ordialing pulse. The FMP 32 may interact through the controller 92 set upthe call conventionally through the modified DLC 70 by way of the TDMmultiplexer 88. Or the signaling data from the subscriber link may betransmitted in the form of DTMF tones which are interpreted eitherthrough a DLC facility or by a detector in FMP 32. The direct mechanismfor handling signaling data is preferred because DTMF tones would takeup bandwidth unnecessarily.

Alternatively, calls can be routed directly to the digital network aspacket data, for example. In such a process, where calls are placeddigitally through the packet network, signaling information may be sentto the NSP 46 along with control information informing the NSP 46 that avirtual circuit for a call is requested. If it is a voice call, a highpriority must be given to the virtual circuit and the NSP 46 must makesure the bandwidth is available. At the time a call is made which is tobe routed directly from the FMP 32 through the packet-switched networks(e.g., SONET or ATM), the FMP 32 may be handling data to and from thesubscribers. At the time the request for a high priority voice channelis made, the ISD 22 has already de-allocated bandwidth assigned for datatransmission to make room for the higher priority voice transmission.The FMP 32 communicates the demand for high priority bandwidth to theNSP 46 and the NSP 36 may deallocate bandwidth formerly dedicated todata transmission (the same data for which bandwidth was de-allocated bythe ISD 22) as it, at the same time, allocates bandwidth for the highpriority call. This may involve a transmission from the FMP 32 to theNSP 46 telling the NSP 46 that less low-priority data bandwidth isneeded in the current call and high priority bandwidth is needed for thenew voice call. The NSP 46 then responds by allocating or identifyingavailable circuits (virtual) and providing the appropriate signaling.When the voice call is finished, similar dialogue between the FMP 32 andNSP 46 takes place. The termination of the call is detected by the FMP32 and a message sent to the NSP 46 informing it that additionalbandwidth is needed for data communications and no (or less) bandwidthfor the voice call.

In the preferred embodiment, the voice and digital information is timedomain multiplexed (TDM) in the digital data stream applied to thedigital filters 82. This embodiment makes it simple and efficient toprovide high priority to voice communications by the ISD 22 by providinga bandwidth on demand as discussed elsewhere in this application and inrelated applications incorporated by reference in this application. Inthe TDM system of the preferred embodiment, it is also convenient tofilter out digitally voice data from the demodulated data streams andapply this data directly to the TDM backplane 90. The latter requiressome discussion regarding routing.

The TDM multiplexer 88 takes the place of multiple line cards. Asmentioned, it is the job of the line cards 96 in a conventional DLC toconvert voice data to digital data and apply it to the TDM backplane 90.In so doing, it will also be the job of the control 92 and thefacilities interface 94 to handle circuit (TDM) to/from packetconversion. In conventional DLCs voice data also includes DTMF toneswhich are decoded in the line cards 96 and used by the controller 92 forcall setup. The same job is performed by the TDM multiplexer 88. Insteadof DTMF tones, the routing data (called number, call origination data,signaling, etc.) are applied in digital form directly to the TDMbackplane 90 for handling by the controller 92. Thus, TDM multiplexer 88creates the appearance of being a line card (or set of line cards) tothe controller and other facilities from the TDM backplane 90 and outthrough the interexchange network. The TDM multiplexer can be plugged asa single card directly into the TDM backplane 90. To the core network(the conventional switched network such as connected through the DLC),all equipment including the NSP 46, the FMP 32 appears to be aconventional DLC. This is advantageous, since there is minimal impact tothe remainder of the network when the equipment is integrated into thenetwork. This configuration provides a seamless interface between thefully digital telephone linked through the ISD 22 and the modified DLC87. It also provides a system that allows packet switched voice and datato work side by side and together with traditional digital loop carrierequipment.

In the preferred embodiment, in the CO to CPE direction, the FMP 32performs the following functions. First, the FMP 32 breaks up thecontrol messages and packets containing user data into segments that fitinto the DSL frames. Secondly, the FMP 32 multiplexes these framestogether with frames containing speech so that the can be transported tothe ISD 22 over the DSL link. Third, the FMP 32 terminates all linklayers associated with the DSL segment of the connection. The reversehappens in the CPE to CO direction. FIG. 5 shows how the access moduletakes information from the DSL modems 201 and places the voice V1, V2,etc. and data D1, D2, etc. into frames 203, then multiplexes the frames203. Consider a scenario where data is fed to the TVRC modems 201 and avoice call comes in. Assume that 1 Mbps is available for informationtransfer via the TVRC modems 201. Prior to the incoming call, all 1 Mbpsis used up. However, as soon as a voice call comes in, since voice has ahigher priority that data, a 64 Kbps channel (slot) is deallocated fromdata usage and is allocated for voice. If a second voice call comes in,then another data channel will be deallocated from data usage andallocated for voice. As the voice call gets terminated, then theallocated voice slots will be reallocated to use by data. Hence, thesystem dynamically allocates bandwidth in real time to maximizeinformation transfer. Note that this time domain multiplexing could beperformed with frequency domain multiplexing, as with a multitonechannel, as well.

Within the local access side of the local loop, multiple FMPs 32 may begrouped and served by a single NSP 46. Each FMP 32 is in turninterconnected to a plurality of ISDs which serves the subscribers in agiven local loop. Usually, the NSP 46 will be located in an AT&TPoint-of-Presence (POP). However, this might not be possible in allareas and it could possibly be co-located with other equipment,depending on space availability.

Although, as discussed above, the TDM multiplexer 90 allows a seamlessinterface between the “old technology” DLC and “new technology”employing the access module 70 and the modified DLC 87 and otherelements of the architecture described here and in related applications,substantial modifications to software of the controller 92 will provideadditional features. These features are discussed here, elsewhere inthis application, and in the related application incorporated byreference in this application. For example, when multiple calls to thesame called party are made, the modified DLC 87 must handle such callsdifferently. In a conventional setup, a message would be sent by the DLC87 that the called party is off-hook. In the current system of theinvention, the called party may still receive additional calls to thesame party. Another example of how software modifications for handlingof voice calls is provided by the voice-activated call example thatfollows, after a discussion of the interaction between the NSP 36 andthe FMP 32. Note that the details of such software modifications are notnecessary to discuss in detail as such are quite straightforward toimplement.

To illustrate the interaction between the various components of theinstant invention, a voice dialing scenario will be described. When asubscriber picks up the telephone and if no digits have been dialedafter a specified period of time has elapsed, the ISD 22 may startdigitizing the voice information into data, for example, 64 Kbps -lawPCM data. The voice samples are then stored in a wave file, which issubsequently transmitted to the FMP 32. On receipt by the FMP 32, theFMP 32 will forward the information to the NSP 36. The NSP 36 willattempt to authenticate the request by ensuring that the subscriber doesindeed have a subscription to the voice dialing service. The NSP 36 candetermine the identity of the subscriber by looking at the address in acertain field of the packet. The NSP 36 can therefore interpret theinformation in the wave files and take the appropriate action. Let usassume that subscriber John wanted to call another subscriber Paul. TheNSP 36 will also attempt to determine who is Paul as defined by John.Once the telephone number for John has been determined, the NSP 36 willinform the FMP 32 to set up a call to John's number. The FMP 32 willthen go through the facilities interface 94 to set up the call. In anembodiment, this would be over TR303 interface and the signal would besent to a DLC to request the local Serving Office to indicate theappropriate ports to use for setting up the call. The FMP 32 has its ownDTMF and tone generator which is used for signaling when theinterexchange carrier network is to be bypassed in routing a call. Forexample, the FMP 32 may be connected to a switched network that requiresthe generation of DTMF signals to set up a call. Such a call can behandled through the FMP 32.

Note that there is a significant advantage implicit in the preferreddesign. The voice dialing service may be provided by a different companyfrom the one that actually connects the call. There is no need to payfor the Local Exchange Carrier (LEC) for providing such a service and itcan all be done with a single facility. Similar services, such as speeddialing, that the LEC provides can now be made available locally.

In the case where there is an incoming call, say from the PSTN, the FMPwill get the information from the DLC. The information will bedispatched over the signaling channel to the NSP 36. The NSP 36 willinstruct the FMP 32 with the information on how the call should beterminated. On receiving this message, the FMP 32 will send theappropriate signaling message to the ISD 22. The ISD 22 “knows” whichphones are in use and which ones are not. As a result, it will applyring to a phone that is free.

In the CPE to CO direction, data “left over” after filtering of voicedata is accomplished by the digital filters 84 is transmitted by theaccess module to the interexchange network. This data includes routingdata as well as content. The link layer interface is provided by thecontroller and multiplexer 84 of the access module 70. Thus, forexample, if the exported data is to be transmitted over an external ISDNinterface, the data from digital filters 82 would be formatted and timedto be applied to such an interface by the controller and multiplexer 84of the access module 70.

In the disclosure of the instant invention, Tethered Virtual RadioChannel (TVRC) is the preferred modulation technique. However, theinstant invention is not limited to the use of TVRC modulationtechnology. However, TVRC would prove to be a major advantage over otherproposed schemes, since it provides an alternate to interleaving whichis used to overcome impairments such as noise and interference and whichresults in unacceptable delays.

Referring to FIG. 4A1, in an embodiment, the FMP 32A, contains a cache85. As described in elsewhere in this application and in relatedapplication incorporated in this one by reference, the hybrid fibertwisted pair local loop architecture permits such services as broadcaststo be conveyed through the interexchange carrier network. For example,movies, radio shows, software and other data services, can betransmitted into the homes and offices of subscribers. To lighten theburden on the interexchange carrier network, frequently requestedbroadcasts or data products or services can be cached in the FMP 32A.Thus, many requests through a single FMP 32A can be handled withoutgoing outside the FMP 32A to route the data.

Although in the embodiments described, the interface between the FMP 32and the ISD 22 employs TDM, other formats for folding the heterogeneousmix of data may be employed. Existing protocols as well as protocols tobe developed may fall within the scope of the present invention and theclaims are not intended to be limited to such a specific communicationformat. In addition, different formats and protocols may be used on thesame link. For example, a portion of the bandwidth of the twisted pairmay be modulated as a multitone signal and a portion modulated as asingle band (e.g., ISDN signal below 40 kHz and discrete multitone, DMT,between 100 kHz and 1 MHz). Alternatively, the lower 40 KHz of the bandmay be utilized for POTS while the remainder of the bandwidth may beutilized for data and/or multiple phone lines.

In addition, although voice communications in an embodiment of the FMP32 are handled conventionally, the FMD 32 provides the capability to usethe digital network directly to transmit voice calls. In such a case,instead of a call being routed conventionally through the modified DLC32, the FMP 32 would notify the NSP 36 that a particular call is a voicecall and the NSP can control the ATM or SONET network to allocatebandwidth to setup the virtual circuit required to support the call.

In addition to monitoring the link between the ISD 22 and the FMP 32 forpurposes of identifying a failure of the ISD 22 (which requireslife-line support), the FMP 32 may provide other line monitoringfunctions, such as off-hook detection, through interaction with theintelligent ISD 22. For example, a subscriber, although the bandwidth isavailable to send an additional call to the same called number, may notwish to have additional calls ring through. The FMP 32 in such a casecould respond to an additional call with a busy signal or voice mail.

Voice information may be transported across a fiber network such as aSONET backbone to a remote switch such as PSTN 46 switch for processingat a remote site. The remote switch may be located in only one of acentral office of a plurality of central offices, whereas the FMP 32 ispreferably located in every central office. This allows the cost of theswitch to be minimized, allowing the use of one switch for a pluralityof central offices. Thus, the architecture is adaptable for the casewhere there is a small percentage of the users in a particular area.

In some embodiments, the FMP 32 may be configured to appear to thenetwork as a conventional DLC. As an alternative configuration, the FMP32 may be configured directly to connect to the ATM without transportacross the SONET network. It may be desirable to transmit the voice datafrom the FMP 32 to the PSTN 42 over a high speed packet network (e.g.ATM, which is superimposed on top of the SONET network. This has anadvantage in that the packet transmission of voice information can bemore efficient than more conventional treatment (for example, it issusceptible to a high degree of compression). However, it requiresadditional management to manage delays, buffer overruns, drop packets,etc., across the ATM network as mentioned above.

As mentioned above, the FMP 32 may connect with a variety of digitalnetworks. Among these may be trunk lines to interconnect nearby FMPs 32.This would allow the FNP 32 to limit traffic on other network facilitiesfor calls destined for nearby FMPs 32. Calls between two subscriberslinked to the same FMP 32 may communicate through the FMP 32 internalnetwork without being linked to any outside network facilities.

The FMP 32 may also programmed to support functions performed by the NSP46 and ISD 22 as discussed above and in related applicationsincorporated herein by reference. For example, software updates for theISD 22 may be transmitted by the NSP 46 to the ISD 22. In such cases,the FMP 32 acts as a conduit merely formatting information packetsbetween the NSP 46 and the ISD 22 if necessary. The FMP 32 may also actas a mere conduit when serving as an internet connection. If datatransmitted over the subscriber line is already in IP form, the FMP 32may not need to repackage the data exchanged between the internet andISD 22. For example, the ISD 22/CPE 10 network may be configured as anintranet. In that case, the FMP 32 may only need to act, for purposes ofcommunicating with the internet, like a dumb data pipeline. However, itmay simultaneously perform its other tasks such as connecting voicecalls, and other kinds of data sessions as discussed above.

Note that, depending on the configuration of the interexchange and othernetworks with which the FMP 32 communicates, signaling andcommunications with the NSP 46 may occur over a different physicaland/or logical network from that handling the voice and user data. Inthe above discussion, the distinction is not made since it is practicaland routine aspect of network design that varies from one network toanother. Thus, for example, communication between FMP 32 and NSP 46 tonotify NSP 46 of a request for bandwidth to be used for a call may occurover one network, a signaling network, while data transmission may occurover a different network used for user and voice data.

Various means can be used to share information about the nature of thedata being transmitted and received at each end of the subscriber link.Many applicable mechanisms may be employed and it sufficient to say thatthe various layers of the subscriber link interact so that both the IDS22 and the FMP 32 keep each other informed about the nature of the databeing transmitted on the subscriber link.

In response to a telephone call originated from a phone connected to theISD 22, the ISD 22 digitizes the telephone DTMF tones, if necessary(since some special phones might not require DTMF decoding). The ISD 22may generated dial tone, if necessary, and translates the signalinginformation as necessary and multiplexes the signaling data, applying itto the subscriber link. High priority bandwidth of the subscriber linkis allocated as discussed above by both the ISD 22 and the FMP 32 actingconcertedly. Bandwidth-on-demand feature is described elsewhere in thisapplication and in related applications incorporated by reference. Modem80 demultiplexes signal data and FMP 32 controller multiplexer 92extracts signaling data and determines how to handle the call by eitherapplying the signaling directly to the DLC 70 backplane 90 via TDMmultiplexer 88 or to an external network through controller multiplexer92 (which could be a separate signaling network). The call also might bedirected through the internal network of the FMP 32 to be connected to asubscriber connected to the same FMP 32 facility. The determination ofwhere to direct the signaling data is made according to the signalingdata itself. It may depend on whether the subscriber subscribes to aservice of a certain carrier whether the call is handled by modified DLC70 as if it were a PSTN. It may depend on whether the call is local orlong-distance. If the call is to be handled on the external networkcontrolled by the NSP 46, the controller multiplexer 92 may respond tothe signaling information by transmitting a request for bandwidth to theNSP 46 and wait for a virtual circuit to be set up. Once the connectionis available, the caller would be signaled by transmitting a ringingsound and subsequently full duplex voice communication over the network.In this case, the FMP 32 simply receives voice data from the network andconverts it to a format appropriate to the subscriber link and feedsdata from the subscriber link to the network, reformatting as necessaryappropriate. When one of the parties hangs up, the FMP 32 may, asmentioned above, indicate this to the NSP 46 so that deallocation andreallocation of network bandwidth. That is, once the call is terminated,a session involving lower priority user data (e.g., internet connectionto a PC of the subscriber) might be allocated more bandwidth in theexternal network because of the increased data flow allocated in thesubscriber line after the termination of the high priority phone call.Where the phone call is patched directly to the TDM backplane 90, thesignaling can be applied as would be generated on the backplane 90 by aline card 96. All the network interfacing is done conventionally in thisinstance. The FMP 32 role is to simply drive the DTM multiplexer 88 asif it were a telephone connected through a line card 96.

Consider now a telephone call generated by a remote party to a partyconnected through the FMP 32 and ISD 22. In this case, because of thefeatures of the architecture discussed in this application and relatedapplications, the telephone call could be an additional call to atelephone number that is already in use. Signaling data would bereceived by the controller multiplexer 92 through either the TDMmultiplexer 88 if the call were received through the conventionaldigital network connected to the modified DLC 70, or from an externalnetwork, which might be a separate signaling portion of the network. Acall generated through the modified DLC 70 would be signaled through theTDM multiplexer 88 to the controller and multiplexer 92. Controller andmultiplexer 92 would then act on the call to simulate a regulartelephone call with the following exceptions: Appropriate signaling datawould be multiplexed and modulated on the subscriber link. The ISD 22would receive the signaling data and send a ring to one or moreavailable phones or answering machines. Upon detection of off-hook, amessage sent to the FMP 32 would be acknowledged and the ISD 22 and FMP32 would create a virtual circuit in the subscriber link to handle thevoice traffic. Upon on-hook detection, a response consistent with therest of this description would be generated in the FNP 32 and ISD 22. Acall through any of the external networks would be handled in the sameway in that signaling would cause the ISD 22 to generate a ring, then avirtual circuit would be established for the duration of the call.Again, a dialogue between the FMP 32 and the NSP 46 may be required tomaximize the efficiency of the use of external network resources. Inaddition to the possibility of connecting through another digitalnetwork via the DLC, the FMP 32, equipped with a sound generator couldconvert the voice data on the subscriber link for transmission over apure analog local exchange carrier or other pure analog network.

The FMP 32 continuously monitors the status of the subscriber link nomatter how much traffic there is on it any time. This can be done inmany ways, such as by sending and receiving test data or dummyinformation or causing subscriber equipment to send status and testresults to the FMP 32. In the event of a failure at the ISD-end of thesubscriber link, the life-line support function of the FMP 32 isinvoked. The controller and multiplexer 92, upon detection of a failureof a type that would prevent a subscriber from communicating overhis/her telephone, throws a switch at the subscriber end of the modem 80to tie the subscriber medium directly to a line card. This switch couldbe invoked by a power failure at either end of the subscriber link andcould be handled external to the controller and multiplexer 92 by adurable and safe mechanism. The ISD 22 has internal hardware andsoftware to insure that at least one POT is directly tied to thesubscriber link medium in the event of such a failure. In this way,life-line support provides POT service through the modified DLC 70 thatis essentially the same as normal service through a conventional DLC.Ringing voltage and power are supplied through a batter to the phone asin normal telephone service.

Note that the band-width on demand feature described in the presentapplication and in the related applications incorporated by referencemay be implemented in a variety of different ways. Foe example, wherethe subscriber link is implemented through discrete multitone modemtechnology, each voice channel could be allocated one or more tones of 4kHz or as required or available depending on the implementation. When avoice virtual circuit is required, a tone-band is deallocated from otherlower priority service and applied to transmit the voice data. This isbasically using frequency division multiplexing as opposed to timedivision multiplexing to separate the various voice data in independentstreams to insure 100% priority (by 100% priority, it is meant that if avoice channel is established, the resources are governed so that itremains 100% open for the duration of the requirement).

The following applications, filed concurrently herewith, are herebyincorporated by reference:

-   1. A Hybrid Fiber Twisted-pair Local Loop Network Service    Architecture (Gerszberg 41-3-13);-   2. Dynamic Bandwidth Allocation for use in the Hybrid Fiber    Twisted-pair Local Loop Network Service Architecture (Gerszberg    42-4-14);-   3. The VideoPhone (Gerszberg 43-9-2);-   4. VideoPhone Privacy Activator (Gerszberg 44-10-3);-   5. VideoPhone Form Factor (Gerszberg 45-11-4);-   6. VideoPhone Centrally Controlled User Interface With User    Selectable Options (Gerszberg 46-12-5);-   7. VideoPhone User Interface Having Multiple Menu Hierarchies    (Gerszberg 47-13-6);-   8. VideoPhone Blocker (Gerszberg 79-38-26);-   9. VideoPhone Inter-com For Extension Phones (Gerszberg 48-14-7);-   10. Advertising Screen Saver (53-17);-   11. VideoPhone FlexiView Advertising (Gerszberg 49-15-8);-   12. VideoPhone Multimedia Announcement Answering Machine (Gerszberg    73-32-20);-   13. VideoPhone Multimedia Announcement Message Toolkit (Gerszberg    74-33-21);-   14. VideoPhone Multimedia Video Message Reception (Gerszberg    75-34-22);-   15. VideoPhone Multimedia Interactive Corporate Menu Answering    Machine Announcement (Gerszberg 76-35-23);-   16. VideoPhone Multimedia Interactive On-Hold Information Menus    (Gerszberg 77-36-24);-   17. VideoPhone Advertisement When Calling Video Non-enabled    VideoPhone Users (Gerszberg 78-37-25);-   18. Motion Detection Advertising (Gerszberg 54-18-10);-   19. Interactive Commercials (Gerszberg 55-19);-   20. VideoPhone Electronic Catalogue Service (Gerszberg 50-16-9);-   21. A Facilities Management Platform For Hybrid Fiber Twisted-pair    Local Loop Network, Service Architecture (Barzegar 18-56-17);-   22. Multiple Service Access on Single Twisted-pair (Barzegar    (16-51-15);-   23. Life Line Support for Multiple Service Access on Single    Twisted-pair (Barzegar 17-52-16);-   24. A Network Server Platform (NSP) For a Hybrid Fiber Twisted-pair    (HFTP) Local Loop Network Service Architecture (Gerszberg    57-4-2-24);-   25. A Communication Server Apparatus For Interactive Commercial    Service (Gerszberg 58-20-11);-   26. NSP Multicast, PPV Server (Gerszberg 59-21-12);-   27. NSP Internet, JAVA Server and VideoPhone Application Server    (Gerszberg 60-5-3-22-18);-   28. NSP WAN Interconnectivity Services for Corporate Telecommuters    (Gerszberg 71-9-74-21-6);-   29. NSP Telephone Directory White-Yellow Page Services (Gerszberg    61-6-4-23-19);-   30. NSP Integrated Billing System For NSP services and Telephone    services (Gerszberg 62-7-5-24-20);-   31. Network Server Platform/Facility Management Platform Caching    Server (Gerszberg 63-8-6-3-5);-   32. An Integrated Services Director (ISD) For HFTP Local Loop    Network Service Architecture (Gerszberg 72-36-22-12);-   33. ISD and VideoPhone Customer Premise Network (Gerszberg    64-25-34-13-5);-   34. ISD Wireless Network (Gerszberg 65-26-35-14-6);-   35. ISD Controlled Set-Top Box (Gerszberg 66-27-15-7);-   36. Integrated Remote Control and Phone (Gerszberg 67-28-16-8);-   37. Integrated Remote Control and Phone User Interface (Gerszberg    68-29-17-9);-   38. Integrated Remote Control and Phone Form Factor (Gerszberg    69-30-18-10);-   39. VideoPhone Mail Machine (Attorney Docket No. 3493.73170);-   40. Restaurant Ordering Via VideoPhone (Attorney Docket No.    3493.73171);-   41. Ticket Ordering Via VideoPhone (Attorney Docket No. 3493.73712);-   42. Multi-Channel Parallel/Serial Concatenated Convolutional Codes    And Trellis Coded Modulation Encode/Decoder (Gelblum 4-3);-   43. Spread Spectrum Bit Allocation Algorithm (Shively 19-2);-   44. Digital Channelizer With Arbitrary Output Frequency (Helms 5-3);-   45. Method And Apparatus For Allocating Data Via Discrete Multiple    Tones (filed Dec. 22, 1997, Attorney Docket No.    3493.20096—Sankaranarayanan 1-1);-   46. Method And Apparatus For Reducing Near-End Cross Talk In    Discrete Multi-Tone Modulators/Demodulators (filed Dec. 22, 1997,    Attorney Docket No. 3493.37219—Helms 4-32-18).

While exemplary systems and methods embodying the present invention areshown by way of example, it will be understood, of course, that theinvention is not limited to these embodiments. Modifications may be madeby those skilled in the art, particularly in light of the foregoingteachings. For example, each of the elements of the aforementionedembodiments may be utilized alone or in combination with elements of theother embodiments.

1. A central office interface between a multiple access link to asubscriber premises and a local carrier network: a digital loop carrierwith a digital interface to permit access to a digital backplane of saiddigital loop carrier; a controller with a modulator/demodulatorconfigured to apply data corresponding to multiple voice call sessionsfrom said link to said digital interface, and to apply datacorresponding to said multiple voice call sessions from said digitalinterface to said link: said multiple access link being established overa single twisted pair metallic interface; wherein said controller isconnected to another digital network; and said controller is configuredto add a new call to said multiple voice call session in response tosignaling data received through said another digital network.
 2. Acentral office interface between a multiple access link to a subscriberpremises and a local carrier network: a digital loop carrier with adigital interface to permit access to a digital backplane of saiddigital loop carrier; a controller with a modulator/demodulatorconfigured to apply data corresponding to multiple voice call sessionsfrom said link to said digital interface, and to apply datacorresponding to said multiple voice call sessions from said digitalinterface to said link: said multiple access link being established overa single twisted pair metallic interface; wherein said controller isconnected to another digital network; and said controller is configuredto add a new call to said multiple voice call session in response tosignaling data received through said link, said controller being furtherconfigured to route selectively said new call through said anotherdigital network responsively to signaling data received through saidlink.
 3. A central office interface between a multiple access link to asubscriber premises and a local carrier network: a digital loop carrierwith a digital interface to permit access to a digital backplane of saiddigital loop carrier; a controller with a modulator/demodulatorconfigured to apply data corresponding to multiple voice call sessionsfrom said link to said digital interface, and to apply datacorresponding to said multiple voice call sessions from said digitalinterface to said link: said multiple access link being established overa single twisted pair metallic interface; wherein said controller isconnected to another digital network; and said controller is configuredto add a new call in said multiple voice call session in response tosignaling data received through said link, said controller being furtherconfigured to route selectively said new call through said anotherdigital network responsively to signaling data received through saidlink; further comprising a data storage unit; and said controller beingfurther configured to route said new call responsively to signaling dataand subscriber data corresponding to said call, said subscriber dataindicating services permitted for a calling party corresponding to saidcall.